Background

A trial was conducted to optimize a 48V battery system at a bank branch in Lagos, installed in August 2023, facing challenges due to overcharging. The system consisted of 24 x 2V 1000Ah VRLA cells, with an average depth of discharge of 60% and an operating temperature of 30°C.


Objective

Identify and rectify issues related to overcharging, aiming to improve battery lifespan, reducing operational costs, and enhance system efficiency.


Methodology

The charging profiles of the battery bank was analysed, focusing on the prolonged charging at 2.35Vpc. Ongoing monitoring and voltage regulation were recommended to prevent overcharging. The trial included assessing total energy throughput, discharge cycles, and operational temperatures.


Findings

The analysis uncovered overcharging issues, risking reduced battery life, thermal runaway, dry out, plate corrosion, increased maintenance costs, and environmental impact. Daily energy losses due to overcharging were calculated at 6.2kWh.


Action Taken
 

Mitigation steps were proposed, emphasizing voltage regulation and ongoing monitoring. Adjustments to charging settings were recommended to align with manufacturer specifications, preventing overcharging.

 

Results

Implementing the suggested changes resulted in extended battery life, projected at 4 years as opposed to 2.5, and reduced energy consumption. Daily savings of $7.12 were estimated, with a return on investment of the enee.io system in just 48 days.